Relationship between accessory foramina and tumour spread in the lateral mandibular surface

The spread of tumour cells to the mandible has been well recognised and invasion of the edentulous alveolar ridge by tumour through accessory foramina has been documented. Tumour infiltration can also occur through the lateral cortical plate, but the number and distribution of accessory foramina on this surface has not been reported. Lateral surfaces of 89 mandibles were examined and accessory foramina which showed a direct communication with the underlying cancellous bone were charted. It was found that the number of accessory foramina varied greatly from specimen to specimen. Only 70.8% of mandibles showed foramina in the coronoid, sigmoid and condylar sections; of these 93.7% exhibited foramina in the condylar section, 23.8% in the coronoid and only 19% in the sigmoid section. This finding confirms that the current practice of conserving part of the ascending ramus posterior to the coronoid process following surgery is sound. Similarly in the rest of the lateral surface, foramina were present in the upper third section in 97.8% of mandibles, 61.8% in the lower third and 58.4% in the middle third sections. This result justifies the principle of rim resection in appropriate cases and the recognition that the alveolar section is commonly invaded before the rest of the body. The number and distribution of foramina may be of greater significance following radiotherapy when the foramina could provide multiple direct channels for invasion of tumour cells from the lateral surface to the medulla.     

下颌骨副孔分布与安全手术切缘的相关性研究

目的：探讨下颌肿瘤及颌周恶性肿瘤经下颌骨副孔浸润传播的途径模式以及治疗下颌肿瘤及颌周恶性肿瘤时下颌骨合理的切除方式。方法：在10-20倍的体视显微镜下观察下颌骨副孔的数量及分布规律，并对26例下颌骨肿瘤病人采用适当的下颌骨手术切除方式。结果：下颌骨内侧面着色副孔的出现率比外侧面的多；在外侧面，下区上部的着色副孔数最多；在内侧面，下区中部的着色副孔数最多。临床手术26例，术后追踪随访23例，19例手术后局部未见肿瘤复发，5年生存率76．9％。结论：（1）下颌骨肿瘤，颌周恶性肿瘤对下颌骨的浸润蔓延与下颌骨副孔密切相关；（2）彻底阻断肿瘤可能经副孔传播的途径，对建立一个真正“安全”的外科手术切缘，对患者的局部复发率和预后的控制均起积极作用。     

下颌骨内侧面副孔的观测及其临床意义

目的 :观测下颌骨内侧面副孔的数量与分布 ,探讨其与肿瘤浸润的关系。方法 :将 74块下颌骨内侧面分为 2区 6部 ,在 1 0～ 2 0倍显微镜下观察各区、部的副孔数量及分布规律。结果 :副孔数量在不同的标本上相差很大 ,平均为 (78.7± 34 .4)个。上区的副孔数比下区的少 ,在上区 ,下颌切迹部副孔数量最多 ,其次为髁突部和冠突部 ;在下区 ,中部副孔数量最多 ,其次为上部和下部。在下颌孔的内侧面副孔的出现率最高 (99.3 % ) ,其次为两侧的颏结节 (72 .8% )、颏结节上方的正中孔 (68.9% )及二腹肌窝(66 .2 % )。结论 :副孔为肿瘤由骨皮质表面进入网状骨质提供了直接通路 ,在下颌孔的内侧面及沿下颌管出现的副孔使这个区域最易受肿瘤播散的侵及     

下颌骨内外侧面副孔分布的比较研究及临床意义

目的　通过对国人下颌骨内外侧面副孔的数量及分布特征的比较研究 ,探讨其与肿瘤浸润的关系。方法　将74块下颌骨的内外侧面分为 2区 6部 ,在 1 0～ 2 0倍显微镜下观察各区、部的副孔数。结果　副孔的数量在不同的标本上相差很大 ,内、外侧面相应各区各部的副孔数比较 ,经U检验 ,P <0 0 0 1 ,差异显著 ,内侧面多于外侧面。结论　副孔为肿瘤由骨皮质表面进入松质骨提供了直接通路 ,内侧面副孔数显然多于外侧面 ,为肿瘤细胞由内侧面骨皮质表面入侵松质骨提供了有利途径     

下颌骨外侧面副孔的观测及其临床意义

目的 :观测下颌骨外侧面副孔的数量与分布 ,探讨其与肿瘤浸润的关系。方法 :将 74块下颌骨内侧面分为 2区 6部 ,在 10～ 2 0倍显微镜下观察各区、部的副孔数及分布规律。结果 :副孔的数量在不同的标本上相差很大 ,平均为 (4 9.4± 2 0 .6)个。上区的副孔总数比下区的少 ,在上区 ,髁突部副孔数量最多 ,其次为冠突部和下颌切迹部 ,平均分别为 (2 .3± 1.8) ,(0 .7± 1.1)和 (0 .3± 0 .7)个 ;在下区 ,上部副孔数量最多 ,其次为中部和下部 ,平均分别为 (12 .5± 6.2 ) ,(5 .0± 3 .8)和 (3 .8± 2 .6)个。结论 :副孔为肿瘤由骨皮质表面进入网状骨质提供了直接通路 ,上部出现的副孔使这个区域最易受肿瘤播散的侵及。     

The clinical anatomy of accessory mental nerves and foramina

Since three‐dimensional computed tomography was developed, many researchers have described accessory mental foramina. The anatomical and radiological findings have been discussed, but details of accessory mental nerves (AMNs) have only been researched in a small number of anatomical and clinical cases. For this article, we reviewed the literature relating to accessory mental foramina (AMFs) and nerves to clarify aspects important for clinical situations. The review showed that the distribution pattern of the AMN can differ according to the position of the accessory mental foramen, and the reported incidence of AMFs differs among observation methods. A review of clinical cases also revealed that injury to large AMF can result in paresthesia. This investigation did not reveal all aspects of AMNs and AMFs, but will be useful for diagnosis and treatment by many dentists and oral and maxillofacial surgeons. Clin. Anat. 28:848–856, 2015. © 2015 Wiley Periodicals, Inc.     

The relationship between the tibialis posterior tendon and the accessory navicular.

Out of a total of 116 cadaver feet, 29 specimens were selected by means of palpation of the tuberosity of navicular for a possible presence of the accessory navicular. They were then radiographed and the accessory navicular was detected in ten. Also three fresh amputation specimens with an accessory navicular were added to the study. A total of 13 legs was dissected and in nine of them, the tibialis posterior tendon inserted directly into the accessory navicular without extending to the sole of the foot. In these feet, the second part of the tibialis posterior tendon originated from the accessory navicular, extending to the normal insertions. There was no connection between these two parts and when traction was applied to either one, no movement was observed in the other. Also a fibrocartilaginous mass was detected in four specimens, probably formed to resist the friction between the tendon and the bone. These results may explain the pronated foot in the presence of the navicular, due to the loss of the function of the tibialis posterior tendon.     

An assessment on spiral CT scan of the superior and inferior genial spinal foramina and canals

To characterise the superior as well as the inferior genial spinal foramen and their bony canal using a large CT data sample. The study included 555 mandibular spirals CT scans, taken from patients for pre-operative implant planning. Basic observation by three observers included the number of canals, their respective anatomical location and morphological variations. Furthermore, linear measurements were performed to describe the foramina and canal characteristics. On spiral CT scans, the superior and inferior genial spinal foramina were detected in 448 CT scans (81%). In 29% of the mandibular CTs, two or more midline canals were noted. 47% of the foramina were located in a position inferior to the genial spines; the others were located in a superior position. The mean (SD) lingual and buccal diameters of the canal structures were 0.73 (0.27) and 0.54 (0.29) mm, respectively with an average length of 3.94 (1.29) mm. The canal was located on average 7.40 (5.31) mm from the mandibular base at the lingual entrance and 7.96 (3.47) mm at the buccal canal end point. The average canal extended towards the buccal bone for an average 37% of the bone width. The results demonstrated the presence of both superior and inferior genial spinal foramina, with 29% of the individuals having double foramina. About 53% of the foramina was located superior to the genial spines. Considering its neurovascular content, these foramina should be carefully evaluated during pre-operative planning.     

The relationship between the medial collateral ligament and the medial meniscus: a topographical and biomechanical study

The functional influence of the medial collateral ligament on the medial meniscus is still discussed controversially. Commonly, a strong fixation of the meniscus by the collateral ligament is described. Injury to the medial meniscus is explained by its reduced mobility due to its strong adherence to the medial collateral ligament. The analysis of 10 plastinated series of the medial femorotibial compartment prove that only few fibres of the ligament radiate into the meniscus. To define the possible contribution of these fibers to the stability of the medial meniscus, experiments on two fresh frozen knee joints were performed. The distal femur was separated by cutting the capsule. The medial collateral ligament was detached carefully from its femoral insertion. The tibial head with both menisci was fixed in a clamping system. A translucent, exact acrylic glass copy of the femoral component to which the medial collateral ligament was reinserted, allowed studying the behaviour of the medial meniscus under axial compression (500 N). Firstly, stress was applied while the collateral ligament was proximally fixed and under tension; then the same experiment was performed after femoral detachment of collateral ligament. All plastinated series revealed only some deep and tender fibrous bundles of the medial collateral ligament radiating into the medial meniscus proximally and posteriorly. The behaviour of medial meniscus was exactly the same in both stress experiment series. The conclusion is that there is no relevant influence of the medial collateral ligament on the stability of the medial meniscus.     

Lingual foramina on the mandibular midline revisited: a macroanatomical study

The purpose of the present study was to determine the incidence, size, location, course, and content of the foramina and bony canals located on the lingual side of the mandibular midline. Fifty dry human mandibles were morphometrically analyzed by measuring the distances of these midline foramina from the mandibular base and the dimensions of these foramina and their bony canals. In addition, macro- and microanatomical dissection was performed on 12 intact cadaver mandibles. The macroanatomic midline foramina were classified into superior and inferior genial spinal foramina according to their vertical location with respect to the genial spines. This study showed that out of 50 dry mandibles, 49 (98%) had at least one midline lingual foramen; only one lacked a true midline foramen. Evaluation of the microanatomical dissections indicated a clear neurovascular bundle in both superior and inferior genial spinal foramina and canals. For the superior canal, the content was found to derive from the lingual artery and the lingual nerve. For the inferior canal, however, the arterial origin was submental and/or sublingual, while the innervation derived from a branch of the mylohyoid nerve. In conclusion, different kinds of lingual foramina have been identified according to their location. The superior and inferior genial spinal foramina have different neurovascular contents, determined by their anatomical location above or below the genial spines.     

下颌管走行弧线与Spee‘s曲线的曲度相关性实验研究

目的 通过对spee’s曲线与作为下颌骨始基的齿槽神经骨管(下颌管)走行弧线曲度的研究找出两者之间有何关系。方法 采用恒牙合初期,颅颌发育正常,恒牙列完整的新鲜头颅的下颌骨30副作为实验对象,用两种不同的分段方法对下颌骨管走行弧线和spee’s曲线的曲度进行测量:①固定弧长(5mm弧长)分段法,②按牙尖解剖和功能特点分段法。结果 按①法测量计算spee’s曲线与下颌管走行整条弧线的曲度无相关性。按②法分段测量计算Spee’s曲线和第二磨牙远中颊尖根连线与下颌管弧线的交点以前的下颌管段,即有牙列存在部分的spee’s曲线与下颌管段的弧线,它们曲线的曲率呈正相关关系,相关系数r=0.8493,P<0.05。结论 spee’s曲线与下颌管走行整条弧线的曲度无相关性,有牙列存在的部分spee’s曲线与下颌管段的弧线,它们的曲度有相关性。     

雌激素与甲状腺癌的关系

 雌激素主要通过其特异受体作用于甲状腺癌细胞。雌激素可以通过其特异受体即雌激素受体（ER）结合雌激素反应因子,激活多种基因影响甲状腺癌细胞生长。以及雌激素通过丝裂原活化蛋白激酶(MAPK)信号转导途径刺激甲状腺癌细胞生长。     

Appearance of the mandibular incisive canal on panoramic radiographs

Panoramic radiographs are routinely used in the dental office for various diagnostic purposes. This study aimed to evaluate the visibility of neurovascular structures in the mandibular interforaminal region on such radiographs. Panoramic radiographs were obtained with a Cranex Tome (Soredex) from 545 consecutive patients using a standard exposure and positioning protocol. For visibility scoring of neurovascular structures, a four-point rating scale was used. The mandibular canal and the mental foramen could be observed in the majority of the cases with good visibility. The lingual foramen was visualized in 71% of the cases, with good visibility in 12%. An incisive canal was identified in 15% of the images, with good visibility in only 1%. An anatomical variation to be considered is the anterior looping of the mental nerve (in 11% of images). Panoramic radiographs can be used for visualization of the mental foramen and a potential anterior looping but not for locating the mandibular incisive canal. To verify its existence for preoperative planning purposes, cross-sectional imaging modalities (HR-CT or spiral tomography) should be preferred.     

The potential effect of anatomic relationship between the femur and the tibia on medial meniscus tears

Background

The anatomic and the kinematical relationships between the femur and the tibia have been previously examined in both normal and diseased knees. However, less attention has been directed to the effect of these relationships on the meniscal diseases. Therefore, we aimed to investigate the impact of femorotibial incongruence on both lateral and medial meniscal tears.

Materials and methods

A total of 100 images obtained from MRI of 100 patients (39 males and 61 females) were included in the study. Diameters of the medial and the lateral femoral condyles, thicknesses of the menisci, and diameters of the medial and the lateral tibial articular surfaces were measured.

Results

The medial meniscus tear was detected in 40 (40 %) patients. However, no lateral meniscus tear was found. Significant relationships were found between the diameters of the posterior medial femoral condyle and the medial tibial superior articular surface and between the diameters of the posterior lateral femoral condyle and the lateral tibial superior articular surface. The mean values for the diameter of the medial condyle of the femur, the lateral condyle of the femur, the medial superior articular surface of the tibia, and the lateral superior articular surface of the tibia were found to be significantly higher in cases with meniscus tear compared to cases without meniscus tear. However, no significant difference was present regarding the thicknesses of the medial and the lateral menisci. A positive relationship between the diameter of the posterior medial femoral condyle and the tibial medial superior articular surface was found in cases with (n = 40) (r ² = 0.208, p = 0.003) and without tear (n = 60) (r ² = 0.182, p = 0.001). In addition, a significant positive relationship was found between the diameter of the posterior medial femoral condyle and the medial tibial superior articular surface in cases with and without tear.

Conclusion

The impact of femorotibial incongruence on the medial meniscus tear is important for the understanding of the lesions.     

Organ‐confined clear cell renal cell carcinoma: the prognostic impact of microvascular invasion,nuclear grade and tumour size

The frequency of diagnosed and treated organ‐confined renal cell carcinoma is increasing. The prognosis of this group of tumours is difficult to predict. The main purpose of this study was to examine the prognostic significance of microvascular invasion, tumour size and nuclear grade in a complete cohort of 76 consecutive patients with organ‐confined clear cell renal cell carcinoma treated with radical nephrectomy. Patient ages ranged from 39 to 88 years (mean 66 years). Median follow‐up was 10.2 years (range 0.1–19.4 years). The tumours were graded according to Fuhrman. Representative histological sections were stained for CD31, which decorates endothelial cells, in order to assess microvascular invasion (MVI). In univariate analysis, microvascular invasion (p<0.01), tumour size (TS) (p=0.01), TNM stage (p=0.01) and Fuhrman nuclear grade (p=0.02) were significant predictors of cancer‐specific survival. Multivariate analysis, adjusted for age, revealed that microvascular invasion, tumour size and nuclear grade were independent covariates. According to our findings microvascular invasion is a strong independent prognostic predictor, and including this in the histopathology report should be considered together with nuclear grade and tumour size.     

Topographical relationship between the accessory hepatic duct and the hepatic artery system

Anatomical Science International - Hepatic biliary injury is one of the most common complications in cholecystectomy and is frequently accompanied by arterial injuries. Because there are several...     

Ⅰ期开窗减压、Ⅱ期刮治术在下颌骨大型囊肿治疗中的应用

目的 探讨采用Ⅰ期开窗减压与Ⅱ期囊肿刮治联合术式治疗下颌骨大型囊肿并保持下颌骨完整性的临床疗效。方法 回顾性分析2011年6月—2013年6月年蚌埠医学院第一附属医院口腔科手术治疗的28例下颌骨大型囊肿患者的临床资料。其中男18例、女10例,年龄9～84岁;囊肿长轴4.5~14.3 cm;牙源性角化囊肿12例,含牙囊肿16例。均采用Ⅰ期开窗减压、Ⅱ期刮治术治疗,术后定期随访,根据临床表现及X线检查评估囊肿缩小的程度。结果 所有患者在Ⅰ期开窗减压术后囊腔均有明显缩小,囊腔内成骨明显。Ⅰ期手术后12～22个月,囊腔变化趋于稳定时行Ⅱ期刮治术。Ⅱ期手术前,口腔曲面体层X线片示:囊腔长轴平均缩小76%。Ⅱ期刮治术后患者下颌骨及牙齿得以保留。28例患者均随访1～3年,平均14个月,随访期间均未见囊肿复发。结论 联合应用Ⅰ期开窗减压、Ⅱ期刮治术治疗下颌骨大型囊肿,既能保存颌骨,又能缩短单独开窗减压术的治疗时间,是下颌骨大型囊肿的优选治疗方法。